Portable power source



FIG. 1 is a front, right, and top perspective view of a portable power source showing our new design;

FIG. 2 is a rear, left, and bottom perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines in the drawings are for the purpose of illustrating portions of the portable power source that form no part of the claimed design. 

CLAIM The ornamental design for a portable power source, as shown and described. 